Tin salts of dimercaptoethyl formal, related compounds and PVC resins stabilized therewith

Abstract

Tin salts formed by the reaction between di-lower alkyl or diaryl tin oxides, and dimercaptoethyl formal and similar dimercapto compounds are disclosed. The final products are useful as ultraviolet light stabilizers for poly(vinyl chloride) resins and for the articles produced therefrom.

The subject matter which applicant regards as his invention is particularly pointed out and distinctly claimed as follows: 
     
       1. A compound of the formula: ##STR3## wherein R is   --(CH.sub.2).sub.m --(OCH.sub.2).sub.p --O --(CH.sub.2).sub.m --(OCH.sub.2).sub.p --O].sub.n (CH.sub.2).sub.m --     wherein p is 0 to 1, m is 2 to about 6 and n is 0 to about 6; and R' is lower alkyl of up to about 10 carbon atoms, or carbocyclic aryl containing 1 or 2 aromatic rings.   
     
     
       2. A compound as defined in claim 1 wherein p is 1. 
     
     
       3. A compound as defined in claim 1 wherein m is 2. 
     
     
       4. A compound as defined in claim 2 wherein m is 2. 
     
     
       5. A compound as defined in claim 1 wherein n is 0. 
     
     
       6. A compound as defined in claim 2 wherein n is 0. 
     
     
       7. A compound as defined in claim 3 wherein n is 0. 
     
     
       8. A compound as defined in claim 4 wherein n is 0. 
     
     
       9. A compound as defined in claim 1 wherein R' is lower alkyl. 
     
     
       10. A compound as defined in claim 1 wherein R' is n-butyl. 
     
     
       11. A compound as defined in claim 8 wherein R' is n-butyl. 
     
     
       12. A light and heat stabilized composition based on poly(vinyl chloride) which comprises: (a) a poly(vinyl chloride) resin; and   (b) a compound of the formula: ##STR4## wherein R and R' are as defined in claim 1.   
     
     
       13. A process for the preparation of a heat and light stabilized composition based on a poly(vinyl chloride) resin which comprises blending with a poly(vinyl chloride) resin an effective amount of a compound of the formula: ##STR5## wherein R and R' are as defined in claim 1.